The present invention relates to a wheel hub and brake disc arrangement for a vehicle wheel, comprising a hub mounted via bearing means on a stub axle, a brake disc non-rotatably mounted on a carrier portion of the hub, and a lock ring axially fixed at an end of the carrier portion, said lock ring having a first side surface lying in contact with a surface on the brake disc and a second side surface, located radially inwardly of the first side surface, said second side surface being in contact with a surface on the hub, and said lock ring permitting, during resilient movement upon axial loading of the brake disc, limited axial displacement of the brake disc relative to the carrier portion.
The invention relates also to a resilient lock ring which is particularly, but not exclusively, intended for a wheel hub and brake disc arrangement for a vehicle wheel.
SE-A-501 006, for example, reveals as previously known a wheel hub and brake disc arrangement, in which the carrier portion of the hub is provided with exterior splines engaging interior splines in a central opening in the brake disc. The brake disc is fixed axially by means of outer and inner lock rings held in grooves in the carrier portion of the hub, of which the inner lock ring axially fixes a resilient ring which has flat parallel opposing side surfaces, one of which having a radially outer portion in contact with a surface on the brake disc and a radially inner portion in contact with a surface of the hub. The resilient ring permits limited axial movement between the disc and the hub to compensate for tolerances and for deformation which occurs in the components involved in braking. The arrangement does not, however, allow for axial pretensioning of the disc, and the result is that. under unfavorable conditions, vibrations can occur during braking.
It is also known to screw a resilient lock ring securely to the wheel hub so that a portion of the side of the ring facing the hub and the brake disc is in contact with the hub and the rest against the disc. The spring distance of the lock ring, i.e. the radial extent of the area between the edge of the surface portion fixed against the hub and the outer edge of the ring, will in this case be relatively short, in a known example circa 3-5 mm. The short spring distance only permits a short axial spring movement which in turn increases the risk of crack formation in comparison to what is the case when there is a long spring distance. Due to the fact that the spring distance is short, the permissible degree of pretensioning is also relatively low.